Advanced Nuclear Technologies Interdisciplinary Research Challenge 2: Develop a transformational fuel for Light Water Reactors – advanced and current.
The US currently has 103 operating nuclear power plants producing over 100 GWe annually. These nuclear reactors are all light-water reactors (LWR) and there are an additional six GWe of LWR capacity under construction. In the world today there are over 435 nuclear power plants, the preponderance of which are water-cooled reactors. There are also over 60 LWR nuclear plants under construction around the world including the US. Given this situation and continued license renewals in the US and in the world, it is safe to say that LWRs will be the dominant technology that is used to produce electricity from nuclear fission reactor plants for several decades.
There is a continued emphasis on improving the reliability and the safety of nuclear power plants. The accident at Fukushima reminded all of us of the need to stay vigilant and seek ways to improve the safety of both existing and new nuclear plants. Even though there were no fatalities from the accident, and its long-term health effects have been estimated to be far less than the tsunami, the economic impact has been huge and the release of radioactive materials off-site can have long-term environmental impact in region surrounding the site.
A direct way to improve the reliability and safety of current and future LWRs, is to focus on novel and transformative advancements in nuclear fuel and cladding design and development. This focus has the best chance of benefiting safety for current and future LWRs for decades.
It is important to consider strategic options, including timeline and budget considerations, for accelerated development and widespread deployment of advanced fuel designs (fuel and cladding) for use in existing (and new) pressurized water reactors (PWRs) and boiling water reactors (BWRs); such that fuel integrity can be maintained in the event of anticipated operational occurrences, and design-basis accidents and the fuel rod is robust under beyond-design basis conditions. This strategy must look broadly at improving fuel performance and safety; e.g., reduction in the generation of combustible gases during fuel degradation. The strategy could consider the use of modern scientific computational tools that could reduce the experimental and development timeline and the steps required for validation of such advanced models. The costs and risks of implementing a new fuel design should be weighed against the costs and risks associated with engineering and administrative changes to the existing systems that could achieve a similar reduction in risk.
The challenge is to develop a coherent plan for developing a novel fuel that incorporates the complete discovery to product process: i.e., R&D plan, fuel demonstration, reliable fuel manufacture, acceptance testing, and performance. This can also provide the opportunity to develop advanced fuels that take the entire fuel cycle implications into account (e.g., spent fuel disposition) to improve upon the current circumstance in which fresh fuels are developed without regard to the implications for the rest of the fuel cycle.
Develop a transformational fuel for Light Water Reactors (advanced and current) that:
Improves the safety performance for the fuel under the range of operating conditions (anticipated operational occurrences and load following), design basis accidents (e.g., LOCA and post-LOCA behavior as driven by stored energy and cladding-coolant compatibility) and special events considered in licensing (e.g., minimized fuel failure in extended station blackout or ATWS, which may be more limiting due to differential responses between fuel and clad);
Can be produced at a cost competitive with the current generation of LWR fuel (as an example, the total cost of a single fuel rod today is about $2500/kg and it produces about 50 MWDth/kg of energy);
As secondary benefits, improves fissile fuel utilization, enhances disposal options, and improves safety performance and reduces costs for spent fuel disposition."
IDR Team members are encouraged to explore ways fundamental advances in material science, nuclear fuels as well as computational modeling can help in these tasks. For example, there have been major advances in multi-scale, multi-component materials modeling that would allow for computational materials design and reduce trial-and-error experimentation. This could transform fuel and cladding design protocols and the novel fuel-clad system could improve behavior during operation and during more extreme environmental conditions.
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